Fuel pump



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FUEL PUMP Filed Deo. 6, 1954 2 Sheets-Sheet 1 April?, 1936.. A M BAWCHEFM www FUL PUMP Filed Deo. 6, 1954 2 Sheets-Sheet 2 I l mw Il Mmmmun"uw Patented Apr. 7, 1936 PATENT OFFICE FUEL PUMP Abraham M. Babitch andGordon W. Harry, Flint, Mich., assignors to General Motors Corporation,Detroit, Mich., a corporation of Delaware Application December 6, 1934,Serial No. 756,257

4 Claims.

This invention relates to pumps and has been designed as an improvedpump for supplying fuel from the fuel reservoir of a motor vehicle tothe engine.

The object of the invention is to provide a pump having superiorcharacteristics such as freedom from leakage, simplicity in the processof assembling the parts, and freedom from noise in operation.

Other objects and advantages will be understood from the followingdescription.

In the illustrated embodiment shown in the drawings the fuel pump isassociated with a vacuum booster pump intended particularly for sup-,-plementing the engine manifold in the operation of a suction motor of anaccessory such as a windshield cleaner.

lin the drawings:

Fig. 1 is a vertical section through the com bined pump structure.

Fig. 2 is a section on line 2-2 of Fig. l.

Fig. 3 is a section on line 3-3 of Fig. 1.

Fig. l is a perspective of the fuel pump valve assembly and the retainertherefor, parts being shown in disassembled relation.

Fig. 5 is a plan view of the rocker arm and linlr assembly.

Referring by reference characters to the drawings, numeral lll is theupper of three casing members, these being preferably made by diecasting. The member ll is recessed on its un.- derside at as i3. To itsupper surface there is secured an inverted cup l5 which may be of glassand which is held against a gasket il by a conventional bail it. The topof the bail carries a screw 2l upon which is threaded a nut ttl, thelatter engaging a cup-shaped stamping t5 in Contact with the glass cupl5 to hold it in position. Within the cup l5 and integral with thecasing ll is a closed air dome 2l. The casing is also formed with a wall29 merging with the wall of the air dome at spaced points marlied a and`b in Fig. 2. Between the spaced points a and b the wall 29 is spacedfrom the wall of the air dome 2l to form a pump inlet space or region3l. The upper wall of member ll also has formed therein an arcuatesediment collecting recess 33. The upper part of the dome 2l togetherwith the wall 29 is formed with a circular ledge 35 upon which issupported the lower and smaller edge of a funnel-shaped ring 3l to thetop of which ring is secured a strainer il@ of wire cloth. A pluralityof peripherally spaced fingers 4I extend from the top of ring 3l andengage the glass cup. The strainer assem- (Cl. 10S-150) bly is thusresiliently held in position. Leading into the space within the glasscup and communicating Withthe region outside the dome 2l and the wall 29is a passage i3 extending through the Wall of casing ll as shown in Fig.2. An inlet pipe from the fuelreservoir is to be secured to the entrancet3. From the region Within the dome 2l an outlet passage 45 extendsthrough casing ll to the wall thereof as shown in Fig. 2. From the endof this passage a conduit is to be connected for communi.` cation withthe carburetor of the engine.

It will now be understood that the recess i3 is the pump chamber, andthat fuel enters it by way of passage 53,. through the screen 39 andthen through space 3l. From the pump chamber the fuel passes into thedome 2l and out through passage 45. Controlling the en- .trance and exitare inlet and outlet valve assemblies. The inlet valve assembly, markedtl, is beneath the flared opening from space 3l leading to the pumpchamber. The outlet valve assembly, marked 69, is in the communieatingpassage from the pump chamber to the dome. The two Valve assemblies, tland t9, are identical in construction and are illustrated in Fig. l andFig. 4. Each valve assembly consists of a disc valve 5l formed to engagea seat 53,- the seat being the smaller diameter part of an aperturedring 55. A stamping 5l has a circular edge 59 bent over and engaging thethe outer face of ring 55. The stamping surrounds the outer periphery ofring and is inwardly bent to engage the opposite face of the largerdiameter portion as shown at lil. 'Ihe stamping is then extended to forma ring portion t3. It is Within this ring portion that the disc valve 5lreciprocates to and from itsseat. The stamping then extends as shown byFig. 4 to form an abutment for the spring 65 of the valve. Inlet valveassembly lll is positioned as shown by Fig. l and Fig. 4 with the face59 engaging the casing wall around the passage between space 3l and thepump charnber. Outlet valve assembly Il!) is inverted so that the facetl engages the annular wall between the pump chamber and the dome 2l. Avalve clamp or retainer 6l, shown in detail in Fig. 4, is provided withopenings for the passage of suitable fastening means by which it may besecured to the underside of casing ll. This clamp has opposite arcuatearms ll and l3. Arm ll engages face 6| of Valve 'll and arm i3 engagesface 59 of valve 49. By this expedient it is unnecessary to makeseparate "vate assemblies. .is single .cs in position. En this wey thecost et manu Lecture is reduced as is also the cost o' assembly andremoval o the valves.

The intermediate pump casing ineinher is designated by numeral Fasteningmeans clamp casing members il and together with the pump diapiu'agintl'ierehetween. Casing member has an inner part il@ `with an aperturedwall di through which the diaphragm stem extends with a small clearance.@Veritoing the wall Si is an oil seal disc @il formed from sott materialsuch as rubberl or leather. lt is positioned by a retainer ill. lheretainer has at its lower end a flange seated on the casing member. Aspring @t engages the retainer at its lower end and a spring guidewasher iii at its upper end. lt may be stated here that this spring ii@is the instrumentality llor producing the discharge stroke oi' the pump.The guide washer lli is seated on shoulder of stem together withdiaphragm protecting washers @3 and 95, the former beneath and thelatter above the diaphragm llt. Above Washer there is press-litted onthe stem. a Washer Sl. Washer @il has a central stepped portion at da.The assembly of dia phragm and Washers is then rigidly secured byriveting or spinning over the hollowed end oi rod. as shown by i. Therecess in. Washer 9i' provided by the stepped construetion taires careof any copper shavings which may be produced when the Wher ispressiitted over the stern which is to be copper= plated. Since Washeris fitted on the stern fixed relationship exists between the position ofthe diaphragm and the :dat on its stern $3, which flat must be correctlypositioned for engagement With operating mechanism as will he explainedbelow.

Beneath intermediate casing l5 is a third casing member This thirdmember is secured to casing 'it by' fastening means iti and a plirsginiii@ is clamped between these casing members. A cap SUE is secured byJasteni means lili to the bottoniL of casing il. s

ills is seated upon a suitable abutment trl casing @s and engagesdiaphragm peotecting Washer iii, the latr seing depressed centrally toposition the spring as at UUS. Washer lili is secured to the phragrn andlower washer by rivets lil winch als scorre additional washer il@ hcentrally disposed raised portion angular in outline at itt. Wltlun thisangular raised portion is seated e. similarly shaped h E23 of stein t lnWay there is no possible leakage through diaphragin lull, and since norelative rotation can occur betwn the stem and the diaphragm fiat faceon the stem l2@ for engagement *mth operating mechanism is definitelylocated by predetermined position of rotation of tl'ie dia ph s1-gn..The lower casing has suitable inlet and outlet openings at itil, 62s. ltalso has inn let and outlet valves, the latter oi which is shovm at itiSince it is old to associate such a second pump with a fuel pump andsince no details of the second pump, in addition to those alreadydescribed, constitute a part of this invention, it is unnecessary tofurther describe the second pump.

The operating means for the two pumps is located in the intermediatechamber llo and a portion of the operating means projects from 'iti intothe engine casing when the casing; h clamped to the engine casing,provision for which is shown by openings G33 in the casing fange A pivotpin lill is press-fitted into casing and extends e/eross an openingflange A bushing it@ is journaled on the pin Journaled for rotation onthe bushing is a rocker arm liti. One end o ann en tends into the pathof movement of cam Mt within the engine casing. The other end oi rocherarm Mi is forked, its furcations Mii and Ml rotatably supported on thebushing i 3Q. Between the furcations M5 and Ml are the jour-- naled endsoi links M9 and Elli. Between these links and also journaled on the samebushing is lil a shorter linlr 53, A. U-shaped link spacer and springseat is shown at it. The legs of this U-shaped spring seat are mountedfor rotation on the bushing i239 and are located between linhs M9 and lland straddle link. E53. Adjacent the bend of the U of member liiti andon the legs are locating lugs im. Cooperating with these lugs is acasing lug i553. The lugs on member W5 and on the casing position aspring Q66. This spring acts to push the member litt whereby it engagesa surface E63 on the rocker arm illi between the furcations and therebyfunctions to keep the rocker arm in contact with the cam. The surface|63 is also adapted to engage the end surfaces of links M9, it, and itl@.t and to swing said links. The engaging surfaces between the links andthe rocker arm afford lost motion connections whereby the pumps mayoperate with variable strokes. The mecharucal mechanism involving therocker arm and the links function to maire the suction stroke oi? thefuel pump and the discharge stroke o." the vacuum pump. The springs andim ser' e to the other strokes of the two pumps. "nlVm td@ and loi arebrought into contact at extreme ends as shown in Fig. 5. The cnrs shapedinto hooked form as may be seen l where they are extended through anonenT the liet portion t6@ ot stern. Mil. the hooked end itl oi' linh:lo interlocltci, 'lith the end it@ of stern @3. lin assembling` theparte it will seen t t the nots on the sten-'is must be positioned asshown, and dats have a fixed relationship to tl phragin in the case oiboth pumps, nredetei positions' of the haphragms will insure coi..- rectrelationship ot the stems with in is desirable that the hot oil shouldme from the crank". oase through the o1 into the pump casing providedior sage oi the rocher arm. Such oil d the diaplu'agm and the oil lossserious. To that end a plate as shown in l'f'ig. 3 is placed over harigelift, its edge resting on in the casing as shown ln Fig. liti an openingElli and the rocker aim lill .As sur faces ill and H9 snugly fitting theupper und lower walls of the seal opening as the onu rotates on itspivot. The side laces of the roc arm engage the side Walls oiP theopening llt. To secure the seal in position there are provided tenons liin the casing ilange. Adjacent these tenons the seal has apertureddepressed regions os at Wfl. After the apertures are positioned tosurround the tenons, the latter are staked over the seal to hold it asshown in Fig. 2. It will be seen that in the staking process the end ofthe tenon is not clamped against the seal. ln this Way slight movemento1' the seal is provided to accommodate any irregularity in the locationof the rocker arm which snugly ilts the opening in the seal as explainedabove. Provision is made for the return of any oil which may enter thepump casing from the crank case. In the lower part of the casing ilangeis a pocket within which any oil passing around the rocker arm maycollect. A flap valve |81 of flexible material and secured to the seal|1| covers an opening |89 communicating with the crank case. This valveis secured by suitable fastening means 9| The oil may return to thecrank case through this valve, but the valve closes against the passageof oil from the crank case.

Among the advantages resulting from the novel pump structure describedabove are the following: The screen is not clamped between covers as inmany prior constructions. Leaking, which would aii'ect priming of thepump, is therefore avoided. The provisions to prevent rotation of thediaphragms relative to their stems is of help in assembling the partsbecause the stems must be located in predetermined positions of rotationto engage the links. The oil sealing devices for the fuel pump stem andfor the passage between the crank case and pump casing effectivelyprevent damage to the diaphragms from heated oil within the crank case.A leak-proof assembly is provided for the connection between the vacuumpump diaphragm and its stem. The sliding contact between the partsrotating on the pivot pin bushing prevents nose. The novel valveassembly is of importance, particularly for purposes of assembly andreplacement. Both valves are alike and assembly and replacement of bothis simultaneously eiected by the attachment or removal of a simpleretainer. The use of the bushing to take the load of the rocker arm andlinks prevents any loosening of the pivot pin in the casing.

We claim:

1. In a pump, a pump casing, a movable pumping member therein, anactuating lever journaled in said casing, projecting therefrom andoperably connected to said movable member. sealing means carried by saidcasing and apertured for the passage oi said lever, said lever beingshaped to continuously fit the aperture of said seal as it rotates, saidsealing means being secured to said casing by means permitting slightmovement thereof to accommodate irregularities in the position of saidlever.

2. In a pump, a pump casing, a movable pumping member therein, anactuating lever journaled in said casing, projecting therefrom andoperably connected to said movable member, sealing means carried by saidcasing and apertured for the passage of said lever, said lever beingshaped to continuously ilt the aperture of said seal as it rotates, saidseal having at its lower end an opening covered by a nap valve to permitpassage of uid from within the pump casing.

3. In a pump, a pump casing, an actuating rocker arm journaled thereinand projecting ABRAHAM M. BABITCH. GORDON W. HARRY.

